The three culprits knocked on the door of a house in Valley Road at 5.45pm on Thursday before going inside.
One man held the bat as all three made demands to the home owner and visiting friends for money and property.
A 17-year-old male was hit with the weapon, causing slight swelling and soreness above the left elbow.
The home owner, a 21-year-old man, was also struck on the head with an iron, which caused swelling and pain.
The iron was also thrown at the third friend in the room, but it missed.
After more demands, the home owner handed over money and the three robbers left, taking a wallet and mobile phone.
Police now want to speak to three culprits and are appealing for witnesses.
The first man, who was was carrying the bat, is described as white, with brown hair, 5ft 10in to 5ft 11in tall and aged between 20-26. He was of a “regular” skinny build and wearing a grey hooded top, grey jogging bottoms and white Nike trainers.
The second is thought to be aged 20-26, white, with brown hair, skinny and approximately 6ft tall. He had a bit of stubble and was wearing a black top with its hood up, black tracksuit bottoms and black trainers.
The third is described as white, about 5ft 7in tall and of a skinny build. He had short white, or very blonde, hair and wore light coloured clothing. He was thought to be slightly younger than the other men.
DI Andy Leonard of Huddersfield CID, said: “This is a particularly unpleasant robbery in which three people simply going about their daily business could have been seriously injured – it is suspected that this is a targeted attack and that no one else in this vicinity is in any way at risk.
“I would appeal to anyone who witnessed the incident or three males acting suspiciously in the area around the time of the incident to contact Huddersfield CID on 101.”